So I have played through the crypts a few times and I have run across two events so far, an endless wave of skeletons that you have to survive and recovering bones for a ghost. Are there any other events here? These two seemed to come with their own achievements which is why I am wondering.

There is an event where you go into the dungeon, and there are mobs named after game developers/producers/etc. and you have to kill the Game Developer Jay who is an elite unburied. This is a feat of strength achievement I've done on Nightmare difficulty.

Do they appear within the crypts in the graveyard though?
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JamesMay 24 '12 at 21:52

@James yes - see my post here gaming.stackexchange.com/questions/69875/… regarding developer hell. It is a completely separate crypt that can spawn in the same area but it is not an "event" as such, more an easter egg with a feat of strength.
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kalinaJun 7 '12 at 13:47